#include <stdio.h>
 
int main()
{
    int murderer[6] = { 0 };
 
    for (int i = 0; i < 6; ++i)
    {
        int is_truth[6] = { 0 };
        int num_truth = 0;
        murderer[i] = 1;
 
        if (!murderer[0])
            is_truth[0] = 1;
        if (murderer[0] || murderer[2])
            is_truth[1] = 1;
        if (!is_truth[0] && !is_truth[1])
            is_truth[2] = 1;
        if (murderer[5])
            is_truth[5] = 1;
        if (!is_truth[2] && !is_truth[5])
            is_truth[3] = 1;
        if (is_truth[0] && is_truth[3] && !is_truth[1] && !is_truth[2] && !is_truth[5])
            is_truth[4] = 1;
 
        for (int j = 0; j < 6; ++j)
            if (is_truth[j])
                num_truth++;
        if (num_truth == 3)
            printf("%c\n", 'A' + i);
 
        murderer[i] = 0;
    }
 
    return 0;
}
